<!DOCTYPE html>
<html>
  <body onload="document.documentElement.offsetHeight; document.getElementById('x').style.position = 'relative';">
    <div style="-moz-column-width: 200px; -moz-column-fill: auto; height: 200px;">
      <div style="height: 150px;"></div>
      <div style="float: left; height: 150px; width: 200px;"></div>
      <div>
        <div id="x" style="float: left; height: 150px; width: 200px;"></div>
      </div>
    </div>
  </body>
</html>
